He expressed hope that political initiatives and talks among Afghan groups without interference of regional and cross-regional countries, arming extremist and terrorist groups, would prevent these attacks which are targeting Afghanistan and its stability and security.

He further said that terrorist attack anywhere, by all group and under any excuse is brutal, reprehensible and unacceptable and should be dealt with firmly.

Qassemi continued that all countries and peace-seeking nations should focus on dealing with extremism, its roots as well as their supporters.

The Islamic Republic of Iran would always stand by Afghan great and oppressed nation, he added.

A powerful bomb hidden in a sewage tanker exploded in the morning rush hour in the center of the Afghan capital on Wednesday, police said, killing at least 80 people, wounding over 350 and damaging embassy buildings.

The victims appeared mainly to have been Afghan civilians.

The bomb, one of the deadliest in Kabul and coming at the start of the holy month of Ramadan, exploded close to the fortified entrance to the German embassy, wounding some staff, German Foreign Minister Sigmar Gabriel said. Pictures showed the embassy building with its windows ripped out.

One Afghan security guard was killed and others were likely among the dead, Gabriel said. A spokeswoman for the German foreign ministry said the bomber's target was unknown.

"Such attacks do not change our resolve in continuing to support the Afghan government in the stabilization of the country," Gabriel said.

Basir Mujahid, a spokesman for city police, said the explosives were hidden in a sewage truck. He also suggested that the German embassy might not have been the target of the blast, which sent towering clouds of black smoke into the sky near the presidential palace.

"There are several other important compounds and offices near there too," he told Reuters.

The blast, which shattered windows and blew doors off their hinges in houses hundreds of meters away, was unusually strong.